echo "Search started.."
for f in $(find / -name "*.pdf" -mtime -10); do 
pdftotext -q $f - | (grep -o '\([345]\{1\}[0-9]\{3\}\|6011\)\{1\}[-]\?[0-9]\{4\}[-]\?[0-9]\{2\}[-]\?[0-9]\{2\}-\?[0-9]\{1,4\}' ; echo "Above data found in file :";echo $f;echo "")>>output.opp
done

for f in $(find / -name "*.pdf" -mtime -10); do 
pdftotext -q $f - | (grep -E -o '\b[0-9]{4}(( |-|)[0-9]{4}){3}\b' ; echo "Above data found in file :";echo $f;echo "")>>output.opp
done

echo "Search completed."
echo "Please refer to output file."